Evaluation of Soil Compaction Characteristics at a Construction Site in Al-Khalis City, Northeast of Iraq

Abstract Soil compaction characteristics namely optimum moisture content and maximum dry density are frequently used as criteria to control field compaction specifications. This study aims to evaluate the compaction characteristics of soil at a construction site located in AL-Khalis City, northeast of Iraq. Ten soil samples were collected from the study area; five samples were augured to perform the Standard Proctor compaction tests to investigate the relationship between the moisture content and the dry density of the soil. A core cutter method was implemented to collect additional five samples used to determine the field dry density of soil and to calculate compaction ratio. The results showed that optimum moisture content values were ranged from 15.4 to 22.5% while maximum dry density values were ranged from 1.63 to 1.83 g/cm 3 . The effect of the compaction effort on the compaction curves was investigated. Increasing the compaction effort increases the maximum dry density and decreases the optimum moisture content of the soil. In addition, a linear relationship between the maximum dry density and optimum moisture content (correlation coefficient R 2 =0.937) is noticed. This relationship is compared with similar relationships from the literature. Finally, compaction ratio, commonly used to evaluate compaction specifications, was calculated. Compaction ratio values indicate that the soil was compacted at the site to satisfactory ranges suitable for engineering construction work.